Gray amber
Gray amber - a substance secreted by sperm whales, has the form of rounded formations consisting of concentric layers with mass reaching hundreds of kg. It has a waxy consistency and pleasant smell when rubbed. Color ranges from ash-gray to black, density is less than that of water. Gray amber should not be confused with yellow amber (succinic acid), which is a mineral resin and falls under commodity position 2530
Source: "Explanations to the Harmonized System of Foreign Economic Activity of the Russian Federation (HS FED Russia)" (prepared by the Customs Union of the Russian Federation) (volume 1, sections I - VI, groups 1 - 29)